TempStr = input("请输入带有符号得温度值是：")
if TempStr[-1] in ['F','f']:
    C = (eval(TempStr[0:-1])-32) / 1.8
    print(C)
elif TempStr[-1] in ['C','c']:
    F = 1.8 * eval(TempStr[0:-1]) + 32
    print(F)
else:
    print("输入格式有误")
